This paper presents a dynamic voltage restorer to solve the voltage sag problem that causes the most serious economic loss among various grid accidents. The proposed method, which uses a direct AC–AC converter, consists of a simple controller unlike methods using a voltage source inverter that is controlled using complex operations. Unlike the energy storage type, there is no additional energy storage device, which reduces system cost. In addition, unlike the back-to-back type, energy conversion loss is reduced by one stage conversion. A switching cell-structured direct AC–AC converter that solves the rectification problem without a separate sensor is a reliable structure that reduces the volumes of the passive filters by increasing the switching frequency. In addition, using interphase voltages, it can take a wide range of voltage compensations to compensate for most of the voltage sag in various situations. In this paper, the background of the study is revealed and the operating principles and control schemes of the proposed system are analyzed. Then, the validity of this study is confirmed through simulation and experiment results.

本文提出了一种动态电压恢复器，以解决导致各种电网事故中最严重的经济损失的电压骤降问题。所提出的方法使用直接的AC-AC转换器，它由一个简单的控制器组成，与使用电压源逆变器的方法不同，该方法通过复杂的操作进行控制。与能量存储类型不同，没有额外的能量存储设备，从而降低了系统成本。另外，与背靠背型不同，能量转换损失减少了一级转换。开关单元结构的直接AC-AC转换器无需单独的传感器即可解决整流问题，是一种可靠的结构，可通过提高开关频率来减少无源滤波器的体积。此外，使用相间电压，在各种情况下，它可能需要大范围的电压补偿来补偿大部分的电压骤降。本文揭示了研究的背景，并分析了所提出系统的工作原理和控制方案。然后，通过仿真和实验结果证实了本研究的有效性。